Is it possible to play saturday morning in Charlotte and catch some afternoon action?

Yes. It's less than 30 minutes from Renaissance to Winthrop. Elon is about 25 minutes from Winthrop. Winget and RLSmith are a bit farther, but good plays depending on what you're looking for. Anyway, very do-able depending on how early you start and how early you want to get to Winthrop.

ProTip: When you get to Rock Hill, take the Cherry Rd exit, but get off Cherry Rd as soon as possible. Get down/over to Eden Terrace via either Patriot Pkwy or N Anderson Rd.